動物都依賴味覺神經系統來攝取營養的食物以及逃避有毒的物質。然而，味覺神經的網路圖譜瞭解仍然非常貧乏。在這份研究報告裡，我們首先瞭解所有已經發表過的味覺受器在腦中的軸突分佈，在進一步的去分析這些軸突分佈的關係。第二我們利用光子活化綠螢光蛋白（PA-GFP）的技術以及果蠅腦神經圖庫來找更多可能的味覺投射神經，我們也預測了可能控制喜好及討厭的腦區，第三我們研發了一個新的果蠅進食的行為實驗，來了解這些可能的味覺投射神經的功能，在一些初步檢測突變的果蠅株後，發現了幾株突變的果蠅是味覺缺陷。我們也同時對控制食慾的神經hugin以及dilp2分析，從型態分佈到釋放的神經傳導物質都做了徹底的瞭解。最後為了能夠徹底瞭解味覺的神經網路，未來的計畫我們將繼續大規模的檢測更多的突變果蠅株來找到更多參與味覺的神經網路，並利用我們進食的行為實驗來驗證這些味覺神經網路的功能。

The gustatory system elicits innate behavior critical for directing animals to ingest nutritious substrate and avoid toxic compound. However, the neural circuits map for gustatory system is still not clear. In this study, Firstly, we analysis the axonal terminal distribution of different GRNs by mapping the expression patterns of the first level of gustatory circuit- gustatory receptors neurons (GRNs) reported from previous studies. Secondly, we trace the candidate gustatory projection neuron by PA-GFP and fly circuit database. We also predict the higher brain center that mediates certain gustatory behavior from neuron morphology. Thirdly, we developed the feeding behavior assay to survey the gustatory circuits in the Drosophila brain. In our preliminary forward genetic screening, found some gene trap lines are identified as a gustatory mutant. Finally, we also map and identify the neurotransmitter release from the gustatory modulatory circuit- hugin and dilp2 neurons. In future, we will screen the gustatory circuit large scale and verify the candidates of gustatory circuits in the secondary level by feeding behavior assay.

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